[1] Leiden Univ, Dept Gastroenterol & Hepatol, Med Ctr, Leiden, Netherlands
[2] Univ Hagen, Dept Hlth Psychol, Hagen, Germany
[3] Univ Utrecht, Dept Clin & Hlth Psychol, Utrecht, Netherlands
[4] LUMC, Dept Rheumatol, Leiden, Netherlands
[5] UMCU, Dept Gastroenterol & Hepatol, Utrecht, Netherlands
[6] UCLA Hlth Syst, Ctr Inflammatory Bowel Dis, Los Angeles, CA USA
[7] LUMC, Dept Med Psychol, Leiden, Netherlands